Connector for electric wires



1944. w. R. MAIN 2,355,387

CONNECTOR FOR ELECTRIC WIRES Filed May 14, 1942 Patented Aug. 8, 1944UNITED STATES PATENT OFFICE 2,855,887 CONNEUI'OR FOB m0 WIRES William 3.Main, Delanco, N. I. Application May 14, 1942, Sada! No. 442,956 11Claims. (01. 174-87) My invention relates to connectors for electricwires, and while it may be employed at various points and for variousconnections to the main or circuit wires, it is particularlyadapted formaking connections between circuit wires at an outlet and the wires of alighting fixture, under a ceiling canopy for lnstsnce,'or at otherpoints, or at an outlet box or for other relatively inaccessiblepositions where it would be a slow and awkward job to make a solderedand/or taped Joint and/or splice.

My invention comprises an improved connector in the form of a pair ofsleeves or shells in longitudinal interfitting position or arrangementand enclosing the bared ends of the wires to be connected, with securingmeans carried by the outer shell or sleeve for permanently holding thewires thereto.

In one form of my improved construction I provide an outer shell orsleeve of relatively heavy material-metal or other suitable substanchhaving a longitudinal opening which may be eccentric to its longitudinalaxis, and such opening receives a shell or sleeve of relatively lightand compressible metalcopper for instance into which the bared ends orthe wires to be connected are introduced; the thicker wall of the outershell or sleeve of this form of my improved construction being providedwith a threaded opening or openings for the reception of a screw orscrews'-preferably socketed elements-whereby, after the ends of thewires have been assembled within the inner lighter sleeve or shell whichhas been previously introduced into the longitudinal opening of saidouter shell or sleeve, the screw or screws may be turned down tocompress and/or crimp the inner metal sleeve or shell against the baredends of the wires contained within thesame; thereby securing the latterin proper electrical contact and in permanent en- Basement with theouter shell or sleeve.

After the connection has been assembled in the manner described, theouter shell or sleeve may be enclosed in a jacket or covering ofinsulating material, with or without the use of a liquid or semi-liquid,air-hardening plastic insulating material at its open end to engage andenclose the wires adjacent to the remaining insulatlng covering of thesame; such open end being then tied or taped with a strip of insulatingmaterial common to electrical wiring practice and providing a waterproofstructure. To facili-' tate application of the insulating jacket orcover, the outer shell or sleeve is quite smooth and the ends thereofhave smooth rounded edges.

5 In another form of connector structure within the scope of myinvention, I may provide an outer sleeve or shell of metal or othersuitable substance which is apertured longitudinally, preferably axiallythereof, and this outer sleeve or shell receives an inner sleeve orshell of compressible metal in the same manner as the other constructionreferred to and is provided with self-contained clamping means arrangedto be forced or upset into engagement with said inner shell or sleevefor the purpose of compressing or crimping the same intermediate itsends whereby the wires contained within the same may be held in properelectrical contact and in permanent engagement with the outer shell orsleeve. This structure will receive an outer Jacket or cover ofinsulating material in the same manner as in the other form of myimproved connector structure.

The inner sleeve or shell, preferably 01' copper, may have a relativelytight fit within the longitudinal opening of the outer shell or sleevein both forms of my improved construction, and with a view of preventingseparation of these parts after assembly, the ends of such inner sleeveor shell may be slightly belledby means of a suitable tool orotherwise-the edges of the openings at the ends of the outer sleeve orshell being slightly rounded to permit this belling or shaping of theends of the inner sleeve or shell.

My improved connecting structure is intended to take the place of whathas come to be known in the electrical wiring art as a "pig-tail splice;

the common or frequent practice heretofore followed being to twisttogether the end of a circuit wire and the end of one of the fixture orother wires to be connected, and then to cover or enclose the ends ofsuch twisted wires with insulating tape. One difllculty with this formof connection is that the tape wrapping frequently comes loose; thejoint is not waterproof-a condition necessitated in many places whereJoints or connections of this general type have to be made-and suchjoint or connection is incapable of taking any strain as might beoccasioned by the breaking loose of a lighting fixture or otherelectrically connected part from any cause..

These and other features of my invention are more fully pointed outhereinafter; reference being had to the accompanying drawing, more orless diagrammatic in character, in which:

Figure 1 is a perspective view of a lighting fixture partially displacedfrom its final position to show connector structures, within the scopeof my invention, between the circuit wires and the fixture wires; suchconnectors being in their final 5 condition of assembly.

Fig. 2 is a longitudinal sectional view of one form of connectorstructure within the scope of my invention; showing the manner ofassembling the wires to be connected therewith.

Fig. 3 is a similar sectional view of a completed connector structure.

Fig. 4 is a cross sectional view, on a larger scale, taken on the lineIV-IV, 1"ig. 3.

Fig. 5 is a cross-sectional view illustrating a detail within the scopeof my invention.

Fig. 6 is a view in elevation and on a larger scale of another form ofconnector structure within the scope of my invention, in which thecrimping or compressing means for the inner wire-containing sleeve orshell is self-contained.

Fig. 7 is a sectional view on the line VII-VII, Fig. 6, showing theself-contained clamping or compressing means, and

Fig. 8 is a similar sectional view showing the clamping or compressingmeans in the operative position of crimping or compressing the innertube or sleeve against the contained wires to be electrically connectedand held in permanent engagement with the outer shell or sleeve.

In Fig. 1 of the drawing 1 have illustrated the application of myimproved electrical connection or splice; such view showing a lightingfixture in one stage of its mounting, the wires A of which have beenconnected to the circuit wires B, by

the connectors C, forming the subject of my in-,

vention; the fixture being now readv to be secured to the backing plateD carried by the wall or other support for such fixture.

In carrying out that form of my invention ilfitted with the set screwsn, which have lustrated in Figs. 2, 3 and 4, I provide an outer 'shellor casing II, which may be of metal, of a dimension approximatingseven-eighths of an inch in length and seven-sixteenths of an inch indiameter-more or less-as may be desired. The outer surface of this shellor casing is smooth and the edges at its ends are preferably rounded asindicated at It. This shell or casing, which -may be cylindrical, isbored at ll, longitudinally of the same, and such bore may be eccentricto its longitudinal axis; the thicker portion of such shell or casingprovided by reason of such eccentricity being tapped and subsequentlythreaded, as at II, for the reception of suitable retainingmembers-which may be socketed set screws, indicated at i3-such screwshaving their inner ends rounded as at It for a purpose hereinafter setforth.

A light metal tube or sleeve, preferably of copper, indicated at It, isinserted in the longitudinal bore ll of the shell or casing l0, and

this inner tube or sleeve receives the bared ends of the wires to beconnected or spliced; the fixture wire being indicated at A and thecircuit wire at B. (In Figs. 2 and 3, the connector is shown asreceiving three wires; since the innertube or sleeve I4 is capable ofcontaining more than two wires, or even more than three wires; acondition that may be necessary in making some types of connections. Fora lighting fixture such as diagrammatically illustrated, the third wireis not needed, and the showing is for illustrative purposes only, toindicate that a group of wires may be accommodated within the inner tubeor sleeve l4, and all retained in electrical contact and in permanentengagement with the outer shell or casing sleeve in the mannerhereinafter set forth.)

The tube or sleeve It is of the same length as the shell or casingsleeve II, and it has a relatively tight fit within the bore i I of thesame. It may be retained in place within the outer shell assess-r i ififge assessable backed away from the longitudinal bore ll, indicated inFig. 2, the metal tube or sleev with the contained wires occupies thefull length osition which may approximate that illustrated in Fig. 3;making a complete electrical connection between said wires and the metaltube or sleeve enclosing the same and permanently engaging the saidinner tube or sleeve and the contained wires with the outer shell orcasing sleeve ll.

After the wires to be electrically connected with their containing tubeor sleeve introduced into the outer shell or casing sleeve have beenconfined by the set screws, I preferably encsse the outer shell oreasing sleeve ll of the connection or splice in a cover or jacket ofsuitable material of an insulating character, indicated at II. This maybe a pocket of fabric treated with a suitable insulating plastic orother body of a similar nature and of a type of material more or lesscommonly in use in the covering of electrical connections. This coveringis waterproof. and the inner end of the same may be tied in place orwrapped around with insulating tape, as indicated at It. I may alsointroduce a fiuid or semi-fiuid body of an insulating plastic at theopen end of the tubular cover or jacket, as indicatedat i1,whichwillbeconfinedinplaceby the tying or taping operation. when thisjacket or cover is employed, a completely waterproof connection isassured.

While I have referred to the use of an outer shell or casing sleeve ofmetal to receive and contain the metal tube or sleeve receiving andcontaining the ends of the respective wires to be electricallyconnected, it is within the scope of my invention to employ a shell orcasing sleeve made of a suitable plastic material; hard rubber,synthetic resins, and/or the like, of a size which may be substantiallythe same as the metal shell or casing sleeve and constructed in allother respects,astoshape.thepositionofthethrough bore, and the aperturesfor the retaining means. asthemetalshellorcasingsleeve. Thethickerportion of such non-metallic shell or casing sleeve will rovidesuificient body for tap l and threading and subsequent application ofthe retaining screws or other holding means.

While I preferably employ an outer shell or casing sleeve of cylindricalcontour in cross-section, it is obvious and that other shapu might beemployed: substantially oval, rectangular, and/or the like, and in Fig.ii I have illustrated. diagrammatically, and in cross-section, a shellor casing sleeve contour, substantially oval, that is within the-scopeof my invention.

In Figs. 6, 'l and 8, I have shown another form of connector structurewithin the scope of my invention in which the retaining means for thecontained tube or sleeve and the wires to be electrically connected andlocated within the same are integral with the outer shell or casingsleeve. .This structure may be cylindrical or of the substantially ovalcross-sectional contour illustrated in Fig. 5, asindicated by the brokenline contour, Fig. 7.

In this construction, the outer shell or casing sleeve, indicated atIII, is cross slotted at intervals throughout its length, as indicatedat lit, and by removing a portion of the metal between nairs'of theseslots at the'upper side of the shell or casing sleeve, as indicated at:r, flanking prongs or fingers Ill are left as shown in Fig. 7, onopposite sides of the through bore Iii receiving the inserted tube orsleeve ill. After the wires to be electrically connected are inserted inthe tube or sleeve ill positioned within the outer shell or casingsleeve Ill, these fingers or prongs may be bent inwardly by a suitabletool and forced against the inner tube or 'sleeve ill; therebycompressing or crimping the wall of the same and the wires containedtherein opposite said fingers or prongs in the manner indicated in Fig.8; thereby holding said wires in electrical contact and in permanentengagement with the outer shell or sleeve casing HI.

After this operation, the shell or casing sleeve H may be encased in aninsulating jacket or cover-similar to that illustrated in Fig. 3, whichwill be secured to the wiresbeyond such shell or casing sleeve in asimilar manner. The slotting of the shell or casing sleeve may beeffected by a saw or a pair of saws set in properly spaced relation tomake the pairs of slots to form the portions from which the prongs orfingers are subsequently formed, and a possible are of cut in indicatedby dotted lines. The removal of metal from the shell or casing sleeve atthe upper side of these portionsconsidering Fig. '1may be effected bydrilling or boring the shell or casing sleeve through to thelongitudinal bore of the same receiving the inserted tube or sleeve Illbefore the cross slots are formed, or in any other suitable manner toproduce the desired result.

If desired, I may employ as the inner tube or sleeve receiving the wiresto be electrically connected any one of a number of connecting tubes orsleeves now in more or less common use and which have a lining of roughgranular materialmetal or other substance-which, upon compression, willbite into the wires and assist in holding them firmly in position.

While I have described the features of my invention with someparticularity and have shown' in the'drawing embodiments of my improvedconnector or splice, it will be understood that such disclosure is forillustrative purposes only and not in any limiting sense sincemodifications may be made without departing from the spirit of myinvention; all of which is deemed to be within the scope of the appendedclaims.

I claim:

1. An electrical connector comprising a pair of tubular members intelescoping engagement; one

of said members being of metal fitting within the other and permanentlysecured thereto: said inner member enclosing a group of wires insubstantially parallel arrangement to be electrically connected, andmeans for compressing the inner member and its contained wires withrespect to the outer member.

2. A connector for electric wires comprising a pair of tubular membersin telescoping engagement; one oi said members being of a compressiblemetal and snugly fitting within the other member and permanently securedthereto: said inner member enclosing a group of wires in substantiallyparallel arrangement to be electrically connected, and means movablewith respect to the outer member for compressing said inner member andits contained wires with respect to said outer member.

3. A connector for electric wires comprising a I I shell, a tubularsleeve telescopically fitting said shell and permanently securedthereto; said tubular sleeve enclosing the ends of a group of wires insubstantially parallel arrangement in be electrically connected, andmeans for compressing the inner tube and the wires contained within thesame.

4. A connector for electric wires comprising a shell, a tubular sleeveof a compressible metal telescopically fitting said shell andpermanently secured thereto; said tubular sleeve enclosing the ends of agroup of wires in substantially parallel arrangement to be electricallyconnected, and means carried by the shell and movable with respect tothe same for compressing the inner metal tube and the wires containedwithin the same.

5. A connector for electric wires comprising a shell having alongitudinal through bore, a tube disposed within said bore andpermanently secured to the shell; said tube being adapted to receiveagroup of wires in substantially parallel arrangement to be electricallyconnected. and retaining means for said inserted wires carried by theshell and positioned to engage'the inserted tube at right angles to thelongitudinal axis of the same.

6. A connector for electric wires comprising a shell having alongitudinal through bore eccentric to its longitudinal axis whereby athickened wall is left at one side of said bore, a tubular sleevedisposed within said bore and permanently secured to the shell; saidsleeve being adapted to receive a group of wires in substantiallyparallel arrangement to be electrically connected, and retaining meansfor said wires comprising screw elements disposed in the thicker wall ofsaid shell for engaging and compressing the inserted sleeve at rightangles to the longitudinal axis of the same.

7. In a structure as set forth in claim 6, screw elements having roundedends for engagement with the inserted tube.

8. A connector for electric wires comprising a shell having alongitudinal through bore eccentric to its longitudinal axis whereby athickened wall is left at one side of said bore, a tubular sleevedisposed within said bore and permanently secured to the shell; saidsleeve being adapted to receive a group of wires in substantially parallel arrangement to be electrically connected, and retaining means forsaid wires comprising screw elements disposed in the thicker wall of theshell for separately compressing the inserted sleeve and the wirescontained within the same.

4 games? 9. A connector for electric wiree comprising e ehell heving elongitudinnl through bore, e oompressibie metnl tube dispoeed withinllld bore and having e relatively tight lit therewith end permanentlysecured to the shell; eeid tube receiving e group of wires ineubetentieily peniielarrangementtobeconnected. endepeiroi screws carriedby the shell in position to engage and crimp themeertedmetel tubeendthewiree contained within the same.

10. A connector for electric vim comprising 1 shell having 1longitudinei through bore; l tube disposed within said bore andpermenently eecuredtotheshelhseidtubebeingedeptedto oi the outer memberat the ends o! it: bore.

WILLIAM it. MAIN.

